Android: Add inspection & quickfix to convert findViewById to api 26

#KT-19940 Fixed Target Version 1.1.5

idea/idea-android/src/org/jetbrains/kotlin/android/inspection/TypeParameterFindViewByIdInspection.kt

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2010-2017 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.android.inspection
+
+import com.intellij.codeInspection.*
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiElementVisitor
+import org.jetbrains.android.facet.AndroidFacet
+import org.jetbrains.kotlin.idea.caches.resolve.analyze
+import org.jetbrains.kotlin.idea.inspections.AbstractKotlinInspection
+import org.jetbrains.kotlin.psi.*
+import org.jetbrains.kotlin.psi.KtPsiUtil.isUnsafeCast
+import org.jetbrains.kotlin.psi.psiUtil.addTypeArgument
+import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
+
+class TypeParameterFindViewByIdInspection : AbstractKotlinInspection(), CleanupLocalInspectionTool {
+    override fun buildVisitor(holder: ProblemsHolder, isOnTheFly: Boolean, session: LocalInspectionToolSession): PsiElementVisitor {
+        val compileSdk = AndroidFacet.getInstance(session.file)?.androidModuleInfo?.buildSdkVersion?.apiLevel
+        if (compileSdk == null || compileSdk < 26) {
+            return KtVisitorVoid()
+        }
+
+        return object : KtVisitorVoid() {
+            override fun visitCallExpression(expression: KtCallExpression) {
+                super.visitCallExpression(expression)
+                if (expression.calleeExpression?.text != "findViewById" || expression.typeArguments.isNotEmpty()) {
+                    return
+                }
+
+                val parentCast = (expression.parent as? KtBinaryExpressionWithTypeRHS)?.takeIf { isUnsafeCast(it) } ?: return
+                val typeText = parentCast.right?.getTypeTextWithoutQuestionMark() ?: return
+                val callableDescriptor = expression.getResolvedCall(expression.analyze())?.resultingDescriptor ?: return
+                if (callableDescriptor.name.asString() != "findViewById" || callableDescriptor.typeParameters.size != 1) {
+                    return
+                }
+
+                holder.registerProblem(
+                        parentCast,
+                        "Can be converted to findViewById<$typeText>(...)",
+                        ConvertCastToFindViewByIdWithTypeParameter())
+            }
+        }
+    }
+
+    class ConvertCastToFindViewByIdWithTypeParameter : LocalQuickFix {
+        override fun getFamilyName(): String = "Convert cast to findViewById with type parameter"
+
+        override fun applyFix(project: Project, descriptor: ProblemDescriptor) {
+            val cast = descriptor.psiElement as? KtBinaryExpressionWithTypeRHS ?: return
+            val typeText = cast.right?.getTypeTextWithoutQuestionMark() ?: return
+            val call = cast.left as? KtCallExpression ?: return
+
+            val newCall = call.copy() as KtCallExpression
+            val typeArgument = KtPsiFactory(call).createTypeArgument(typeText)
+            newCall.addTypeArgument(typeArgument)
+
+            cast.replace(newCall)
+        }
+    }
+
+    companion object {
+        fun KtTypeReference.getTypeTextWithoutQuestionMark(): String? =
+                (typeElement as? KtNullableType)?.innerType?.text ?: typeElement?.text
+    }
+}

idea/idea-android/tests/org/jetbrains/kotlin/android/TestUtils.java

@@ -34,6 +34,6 @@ public class TestUtils {
 
     @NonNull
     public static String getLatestAndroidPlatform() {
-        return "android-25";
+        return "android-26";
     }
 }

idea/idea-android/tests/org/jetbrains/kotlin/android/lint/AbstractKotlinLintTest.kt

@@ -16,6 +16,7 @@
 
 package org.jetbrains.kotlin.android.lint
 
+import com.intellij.codeInspection.InspectionProfileEntry
 import com.intellij.testFramework.fixtures.impl.CodeInsightTestFixtureImpl
 import com.intellij.util.PathUtil
 import org.jetbrains.android.inspections.klint.AndroidLintInspectionBase
@@ -53,7 +54,7 @@ abstract class AbstractKotlinLintTest : KotlinAndroidTestCase() {
 
         myFixture.enableInspections(*inspectionClassNames.map { className ->
             val inspectionClass = Class.forName(className)
-            inspectionClass.newInstance() as AndroidLintInspectionBase
+            inspectionClass.newInstance() as InspectionProfileEntry
         }.toTypedArray())
 
         val additionalResourcesDir = File(ktFile.parentFile, getTestName(true))
@@ -76,6 +77,6 @@ abstract class AbstractKotlinLintTest : KotlinAndroidTestCase() {
             myFixture.copyFileToProject("${PathUtil.getParentPath(path)}/$dependencyFile", "src/$dependencyTargetPath")
         }
 
-        myFixture.checkHighlighting(true, false, false)
+        myFixture.checkHighlighting(true, false, true)
     }
 }

idea/idea-android/tests/org/jetbrains/kotlin/android/lint/KotlinLintTestGenerated.java

@@ -66,6 +66,12 @@ public class KotlinLintTestGenerated extends AbstractKotlinLintTest {
         doTest(fileName);
     }
 
+    @TestMetadata("findViewById.kt")
+    public void testFindViewById() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/testData/android/lint/findViewById.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("javaPerformance.kt")
     public void testJavaPerformance() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/testData/android/lint/javaPerformance.kt");

idea/idea-android/tests/org/jetbrains/kotlin/android/quickfix/AndroidLintQuickfixTestGenerated.java

@@ -36,6 +36,27 @@ public class AndroidLintQuickfixTestGenerated extends AbstractAndroidLintQuickfi
         KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/android/lintQuickfix"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), TargetBackend.ANY, true);
     }
 
+    @TestMetadata("idea/testData/android/lintQuickfix/findViewById")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class FindViewById extends AbstractAndroidLintQuickfixTest {
+        public void testAllFilesPresentInFindViewById() throws Exception {
+            KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("idea/testData/android/lintQuickfix/findViewById"), Pattern.compile("^([\\w\\-_]+)\\.kt$"), TargetBackend.ANY, true);
+        }
+
+        @TestMetadata("nullableType.kt")
+        public void testNullableType() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/android/lintQuickfix/findViewById/nullableType.kt");
+            doTest(fileName);
+        }
+
+        @TestMetadata("simple.kt")
+        public void testSimple() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/android/lintQuickfix/findViewById/simple.kt");
+            doTest(fileName);
+        }
+    }
+
     @TestMetadata("idea/testData/android/lintQuickfix/parcelable")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)